1. FIELD OF THE INVENTION
The present invention relates to an adjustable stool and, more specifically, to an adjustable stool where the height of the stool can be varied by using foot switches mounted on the top surface of the device, allowing the hands of the user to be free to pursue the current work being engaged therein.
2. DESCRIPTION OF THE PRIOR ART
In a number of fields it is desirable, for both comfort and utility, to be able to adjust the height at which one is standing. For example, doctors and other operating room personnel, during a long procedure, may wish to change their positional attitude with respect to the patient. Extended periods of bending can lead to unnecessary fatigue and/or discomfort that, in the interest of safety and occupational satisfaction, should be minimized. The medical community is not, of course, the only fraternity with this problem. Any field where the work is, by necessity or custom, performed in a standing posture confronts this hazard. Bending over, even slightly, for protracted periods of time without relief can lead to chronic back problems, or exacerbate an already existing condition.
U.S. Pat. No. 3,472,183 issued on Oct. 14, 1969 to Robert Goodman addresses this issue and discloses a vertically adjustable table wherein a motor means controlled by a switch drives an internally threaded jack screw cylinder allowing the table to be adjusted in small increments.
U.S. Pat. No. 4,232,901 issued on Nov. 11, 1980 to Elaine M. Harrington et al. discloses an adjustable ottoman where a remotely located switch engages an electric drive system to turn a pair of chains, which, for their part, are attached to two threaded rods. By means of two sets of bars fixed to a lazy tongs arrangement, the ottoman is adjustable in respect to a vertical plane.
U.S. Pat. No. 3,982,718 issued on Sep. 28, 1976 to Richard P. Folkenroth et al. discloses an operatory chair that, using a pair of lazy tong assemblies and a threaded rod adjacent to the base of the device, can be adjusted as to height.
U.S. Pat. No. 3,024,738 issued on Mar. 13, 1962 to Phil J. O'Toole et al. discloses a mobile, collapsible display device. The device has a wheeled base, a number of telescoping sections, and is raised or lowered by a piston extending from a cylinder that is attached to a pair of pivoted levers. There are a pair of X-frame stabilizers on either side of the device, and the top is equipped with a turntable to facilitate the display of an automobile or the like.
U.S. Pat. No. 3,700,070 issued on Oct. 24, 1972 to John Calaby King discloses a scissors-type linkage where, when the linkage is in the fully collapsed position, the pivot point is above the line of action of a horizontally positioned hydraulic cylinder, overcoming the problem of a high initial force requirement.
U.S. Pat. No. 4,858,482 issued on Aug. 22, 1989 to Erik Knudsen and U.S. Pat. No. 4,934,647 issued on Jun. 19, 1990 to James S. Edwards both show scissor-type mechanisms for lift tables or universal mounts, respectively.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.